Answer:
(a) see attached
(b) Surface area = 224 mm²
Step-by-step explanation:
A square based pyramid is made up of a square at the base and 4 congruent triangles as the sides which meet at one point.
Area of a triangle = 1/2 × base × height
⇒ area of one triangle = 1/2 × 8 × 10
= 40 mm²
Area of a square = s² (where s is the side length)
⇒ area of base = 8²
= 64 mm²
Total surface area = 4 × area of one triangle + area of the base
= 4 × 40 + 64
= 224 mm²
